Apparatus for manufacturing a plastic name tag holder

ABSTRACT

This invention includes apparatus for manufacturing a plastic name tag holder. The preferred name tag holder is rectangular and has a central cavity open at one end for insertion of the name tag. The holder has a rigid plastic bottom sheet and a rigid plastic parallel top sheet which is turned down around three sides of its periphery and is sealed to the bottom sheet on three sides to provide the central name tag slot. The slot is substantially rectangular in vertical cross-section. 
     The apparatus for manufacturing a plurality of name tag holders includes hinged horizontal insert fingers mounted on the lower platen to separate the top and bottom vinyl sheets and to provide a plurality of male molds corresponding to the central cavities. A plurality of U-shaped electrode dies draws the top sheet down and around the U-shaped insert fingers and seals the top sheet to the bottom sheet beyond the perimeter of the insert fingers. The electrode dies also cut the top and bottom sheets between the insert fingers so that after the sealing and cutting are completed, the operator can strip away the waste with one motion and can then remove the completed name tag holders from the insert fingers.

BACKGROUND OF THE INVENTION

Plastic name tag holders, such as are used on luggage, are usuallyformed by placing an insert between two flat plastic sheets,electronically heat sealing the sheets around the insert periphery, andthen removing the insert. The sealing is effected by opposed flatenergized surfaces. This type of tag holder has a small almond-shapedpocket or cavity into which a name tag or card may be inserted. Thesealed edges are flat and the central cavity has a diminishing verticalcross-sectional area or "pinched effect" as it approaches the sealededges. The use of flat plastic sheets limits the height of the insertthat may be used, and makes the name tag insertion process quitedifficult. These problems exist whether or not the plastic sheets aresoft, semi-rigid, or rigid.

SUMMARY OF THE INVENTION

It is an object of this invention to provide apparatus for manufacturinga plastic name tag holder which has parallel top and bottom rigidsheets.

It is another object of this invention to provide apparatus for sealinga plurality of name tag holders simultaneously.

It is another object of this invention to provide apparatus formanufacturing name tag holders which operates in a fast, efficient,inexpensive, simple, and long-lasting manner.

The preferred name tag holder has parallel flat top and bottom sheetsand has a substantially rectangular vertical cross-section. A slot isprovided for a fastening strap and the edges and corners are smoothedand rounded, respectively.

The preferred apparatus includes a lower platen, hinged flat insertfingers, having U-shaped perimeters, mounted on the lower platen, andseveral U-shaped electrode dies mounted on the upper platen and beingheated and electrically energized to produce a radio frequency signalfor sealing purposes. Rigid plastic top and bottom sheets are placedabove and below the insert fingers, respectively, and the electrode diesare lowered to draw the top sheet down and around the insert fingers(with the assistance of compression blocks which maintain the top sheetflat against the upper surfaces of the insert fingers). The dies sealthe top and bottom sheets together around three sides of the insertfingers and cut the sealed sheets between the fingers by forming aso-called tear line. The dies are raised, the scrap is stripped awaywith one motion, and the name tag holders are removed from the fingers,ready for slotting (for a fastening strap) and for edge smoothing, ifnecessary.

The insert fingers determine the central cavity shape and dimensions,and also hold the sealed name tag holders in place while the scrapmaterial is being stripped away.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation of the dielectric sealing machine showingthe preferred embodiment of the manufacturing apparatus attached to theupper and lower mounting plates of the sealing machine.

FIG. 2 is a front perspective view of a portion of the electrode dies,the compression blocks, and the hinged insert fingers.

FIGS. 3a, b, and c are front elevations illustrating the sequentialsteps of sealing and cutting the name tag holder.

FIG. 4 is a perspective view showing the manual stripping of excesssheet materials after the name tag holders have been sealed and cut.

FIG. 5 is a perspective view, partly cut away, showing the completedname tag holder.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 shows (in dotted outline) a conventional dielectric sealingmachine 10 of the type currently obtainable from Cosmos ElectronicMachine Corp. of New York, N.Y. Such a machine has the followingoperating characteristics: 220 AC volts; 60 AC amps/leg; 50-60 cycle ACfrequency; 96 power factor; 10 KW HF output power; 27.12 MC highfrequency; and 3 Phase. The sealing machine has a conventional uppermounting plate 11 and a lower mounting plate 13.

An upper platen 12 and a lower platen 14 are secured to the uppermounting plate 11 and the lower mounting plate 13, respectively. Plate11 and platen 12 are electrically and thermally connected together andare conductive.

A plurality of electrode dies 16 is secured to the upper platen 12.Preferably, there are a total of eight dies arrayed in two opposinglines of four dies each. As shown in FIG. 2, each die 16 has a U-shapeand has a downwardly extending peripheral portion which is divided intoan outer periphery 18 terminating in a sharp cutting edge 20, and aninner periphery 22 terminating in a flat sealing edge 24. A clearancespace 26 divides the inner periphery 22 and its sealing edge 24 from theouter periphery 18 and its cutting edge 20. All of elements 18, 20, 22,24 and 26 are U-shaped in horizontal cross-section and it will be notedthat the plane of cutting edge 20 is vertically lower than the plane ofsealing edge 24. Die 16 can be described as a tear seal die with a stepbetween the upper sealing edge and the lower cutting edge.

Also secured to the upper platen 12 is a compression block 28. Thisblock is preferably a block of non-conductive polyurethane foam, and theplane of its flat lower bearing surface, when uncompressed, isvertically below the plane of cutting edge 20. In the preferredarrangement of eight U-shaped electrode dies 16 (the bottoms of four U'sbeing adjacent to the bottoms of the other four U's), there are eightfoam blocks 28 within the eight dies 16. Thus, there are two rows offoam blocks, four blocks in each row.

Referring now to FIGS. 2 and 4, it will be seen that a male moldassembly 30 is mounted on the lower platen 14 and consists of two hinges34 having four hinge sections. Two of the hinge sections are quite smalland are bolted to the lower platen 14. The other two hinge sections eachhave the form of four pivotable insert fingers 32, preferably made ofbrass or other easily formed material. The insert fingers have U-shapedperimeters, the bottoms of which are adjacent to each other in two rowsof four (see FIG. 4). Preferably, each finger is approximately 46 mm.wide and 1 mm. thick.

The hollow U-shaped dies 16 are slightly wider (horizontally) than arethe insert fingers 32 and are in vertical registration with them. Thus,when the two platens are moved vertically towards each other, the innerperiphery 22 of the die 16 passes to the outside of the outer perimeterof the insert finger 32. In other words, each insert finger 32 fitswithin the hollow of each die 16.

The operation of the dielectric sealing machine will now be described sothat the method of manufacturing the plastic name tag holders will beunderstood. The machine is initially placed in its start position withmounting plates 11 and 13 moved to their positions of maximum verticalseparation. Then, insert fingers 32 are lifted and the bottom plasticsheet 42 is placed on lower platen 14 between alignment blocks 40. Theinsert fingers are then lowered to the horizontal and the top plasticsheet 44 is placed over the insert fingers within the confines ofalignment blocks 40.

Preferably, bottom sheet 42 is a rigid polyvinyl sheet having athickness of approximately 1 mm. and is either opaque or transparent.However, the range of bottom sheet thicknesses could certainly run fromapproximately 0.1 mm. to 4 mm. Preferably, top sheet 44 is also a rigidpolyvinyl sheet having a thickness of approximately 0.5 mm. and istransparent. However, the range of top sheet thickness could certainlyrun from approximately 0.25 mm. to 1 mm. These ranges are not intendedto be limitations and are mentioned merely as examples.

The upper mounting plate 11 is then lowered, thereby bringing the foamcompression block 28 down into contact with top vinyl sheet 44 (see FIG.3a). As the foam block compresses, sheet 44 is held downwardly againstthe insert finger 32 and is stabilized against lateral movement. Theupper mounting plate continues to be lowered so that the cutting edge 20of die 16 contacts top sheet 44 and presses it against bottom sheet 42(see FIG. 3b). This causes the top vinyl sheet 44 to bow upwardly to alimited extent.

At this point, the sealing step is begun. The dielectric sealing machine10 has energized the electrode die 16 so that it is heated to athermostatically controlled temperature of 110° to 120° C. This enablesthe cutting edge 20 to easily sink downwardly into the overlying top andbottom sheets while simultaneously heating and softening the sheetsthemselves. This permits the top sheet to be urged back into the shownhorizontal attitude.

The sealing edge 24 has meanwhile drawn the top sheet down around theU-shaped perimeter of the insert finger 32 and has flattened theperimeter of the top sheet horizontally against the bottom sheet. Theheated dies and their sealing edges are then energized with a highfrequency radio signal by the generator of the sealing machine so thatthe sealing edges act as electrodes to seal the top sheet to the bottomsheet with a U-shaped bond. A satisfactory electrode operating signal isproduced when the sealing machine 10 has a power factor of 96, afrequency of 27.12 MC, and a three-phase signal.

FIG. 3c shows the sealing step position. The cutting edge hassubstantially cut through the top and bottom sheets to form a U-shapedtear line 49. The heated sealing edges have been electronicallyenergized for a time period of approximately 8 to 11 seconds to softenand bond the top sheet to the bottom sheet in the perimeter area 50. Thebonding action has caused the plastic to flow and to form a smallcontinuous shoulder 51 in the clearance space 26 between the cuttingedge and the sealing edge.

Best bonding results have been obtained when the radio frequency signalhas been controlled to gradually increase in strength and then togradually decrease in strength over the sealing period. During thistime, the temperature is held constant. Then, after the sealing step hasbeen completed, the HF signal is terminated, and the bonded sheets arepermitted to cool for a period of 1 to 2 seconds.

FIG. 3c shows the top sheet 44 turned down around its perimeter area 46and turned out around its perimeter area 50. For purposes of clarity,the drawings show a space between insert finger 32 and top sheetperimeter area 46, and also show perimeter area 46 to be somewhatcurved. In fact, top sheet perimeter 46 is drawn down quite close to theinsert finger 32 and becomes almost a vertical wall at right angles totop sheet 44 and bottom sheet 42.

After the sealing and cooling steps have been completed, the uppermounting plate is raised, thereby removing die 16 and foam block 28 frominsert fingers 32. Now, the machine operator grasps the vinyl waste, asshown in FIG. 4, and strips it away in one continuous motion. The wastetears along tear lines 49 and leaves eight virtually completed name tagholders 52 still seated on the eight insert fingers. The name tagholders are then manually removed from the insert fingers.

FIG. 5 shows the completed holders 50 after they have been removed fromthe insert fingers. The central cavity or slot 54 is substantiallyrectangular in vertical cross-section with the top sheet 56 disposedparallel to bottom sheet 58. Side wall 46 is substantially vertical andis perpendicular to the top and bottom sheets. The name tag holder issubstantially rectangular in plan view.

Several finishing operations may now be performed. A slot 60 may bepunched vertically through the sheets 56 and 58 to accommodate afastening strap. The peripheral edges may be smoothed and the cornersrounded. Finally, advertisements or the like may be printed on the lowersurface of bottom sheet 58. The name tag holder is now completed andready for packing and shipping.

As a variation, instead of a single top and a single bottom sheet, twotop and two bottom sheets could be used, one pair for each set of hingedinsert fingers. Then, the operator would strip the waste in two separatemotions.

In the preferred embodiment, polyvinyl chloride sheets of specifiedthicknesses were described. Such sheets would typically have a tensilestrength of between 5-9,000 psi, a percentage elongation of from2.0-40.0, a tensile modulus of from 3.5-6.0 × 10⁵ psi, a compressivestrength of from 8,000-13,000 psi, and an impact strength of 0.4-20.0ft.-lb. per inch Izod test. Other sheet materials having the samegeneral mechanical characteristics, such as other vinyl polymers andco-polymers (for example, vinyl chloride acetate, vinylidene chlorideand ABS-modified vinyl chloride) may be substituted if carefullyselected.

The above description obviously suggests many possible variations andmodifications of this invention which would not depart from its spiritand scope. It should be understood, therefore, that the invention is notlimited in its application to the details of structure specificallydescribed or illustrated and that within the scope of the appendedclaims, it may be practiced otherwise than as specifically described orillustrated.

I claim:
 1. For use with a dielectric sealing machine, apparatus forsealing plastic name tag holders and the like comprising:a. an upperplaten having at least one electrically energized substantially U-shapedhollow electrode die secured to its lower surface, said die having adownwardly extending outer periphery terminating in a horizontalsubstantially U-shaped lower cutting edge, said die also having adownwardly extending inner periphery terminating in a horizontalsubstantially U-shaped lower sealing edge, the plane of said cuttingedge being disposed below the plane of said sealing edge; b. compressionmeans secured to the lower surface of said upper platen within saidhollow die, said compression means having a lower substantiallyhorizontal bearing surface which, in its uncompressed condition, isdisposed below the horizontal plane of said cutting edge of said outerperiphery; and c. a lower platen underlying said upper platen, saidlower platen having a male mold assembly secured to its upper surface,said male mold assembly having at least one substantially planar insertfinger having a substantially U-shaped perimeter, said insert fingerbeing slightly narrower than said electrode die, said insert fingerbeing normally positioned horizontally in telescopic registrationbeneath said electrode die, said insert finger being movably attached tosaid mold assembly to permit a bottom sheet of plastic to be insertedbetween said insert finger and said lower platen, and to permit a topsheet of plastic to be positioned over said insert finger; d. said upperplaten being lowered by said dielectric sealing machine to cause saidcompression means and said die to contact the top plastic sheet, saidcompression means urging the top plastic sheet into a horizontal planeagainst said insert finger, said substantially U-shaped sealing edgedrawing the top sheet down and electronically sealing it to the bottomplastic sheet beyond the perimeter of said insert finger, and saidsubstantially U-shaped cutting edge cutting the sealed top and bottomsheets further beyond the perimeter of said insert finger, said upperplaten being raised to permit the cut-off sheet waste to be strippedaway and the completed name tag holder to be removed from said insertfinger.
 2. The sealing apparatus of claim 1 wherein said electrode dieis also thermally energized.
 3. The sealing apparatus of claim 1 whereinsaid inner die periphery is horizontally spaced from said outer dieperiphery and defines a clearance space therebetween.
 4. The sealingapparatus of claim 1 wherein said upper and lower platens are secured toupper and lower mounting plates, respectively, of the dielectric sealingmachine.
 5. The sealing apparatus of claim 1 wherein said compressionmeans comprises a block of polyurethane foam.
 6. The sealing apparatusof claim 1 wherein said male mold assembly comprises a plurality ofparallel insert fingers, said insert fingers being hingedly attached tosaid lower platen to normally lie in the horizontal plane, said insertfingers being vertically aligned in telescopic registration beneath saiddies.